1. Field of the Invention
The invention relates to a storage apparatus and a data protection method, for example, one that is suited for use in a storage apparatus having the AOU (Allocation on Use) function.
2. Description of Related Art
Some data stored in storage apparatuses is required by laws or company rules to be kept for a certain period of time. Depending the type of data, it is sometimes required to keep data for several years or decades (or more as the case may be).
In light of the above circumstances, in recent years, in JP-A-2005-18568, the applicant of the present application proposed a method for setting an access attribute for each volume (read access permission/prohibition, write access permission/prohibition, etc.) in order to prevent unauthorized access to volumes in a storage apparatus from a host apparatus, which is a higher-level system.
Meanwhile, when a user wishes to extend the capacity of a logical volume, he/she needs to contact the logical volume provider. However, if multiple users simultaneously make logical volume extension requests to a large-scale site like a data center, which multiple companies jointly use, the logical volume provider cannot fully respond to those requests, and in the worst-case scenario, the processing in the logical volume provider's host apparatus may halt.
In light of that, in JP-A-2003-15915, the applicant of the present application also proposed a method for dynamically allocating a storage area with an appropriate capacity from among collectively managed storage areas to a logical volume as a method for easily extending a logical volume capacity.